Tamper proof seal for a container

ABSTRACT

Lid for a container holding fluid contents, having an opening for pouring and an opening for admitting air. These openings are sealed on the side of the lid facing out from the container, with a strip of foil joined to the lid. The strip of foil exhibits a feature of originality to show that the container has not been opened in any way at these openings.

United States Patent [191 Langen 1 Dec. 23, 1975 TAMPER PROOF SEAL FOR A CONTAINER [75] Inventor: Hanno Langen, Gottmadingen,

Germany [73] Assignee: Swiss Aluminum Ltd., Chippis,

Switzerland [22] Filed: Apr. 10, 1974 211 App]. No.: 459,475

[30] Foreign Application Priority Data Apr. 13, 1973 Germany 2318668 [52] US. Cl 220/266; 220/359; 229/7 R; 229/51 AS; 206/459 [51] Int. Cl. B65D 41/32; B65D 41/00 [58] Field of Search 220/359, 266; 229/51 AS, 229/7 R; 206/459; 215/7, 250, 253, 254

[56] References Cited UNITED STATES PATENTS 3,312,368 4/1967 Reynolds et al. 220/359 3,616,898 11/1971 Massie 206/459 Primary Examiner-George T. Hall Attorney, Agent, or Firm--Ernest F. Marmorek [57] ABSTRACT Lid for a container holding fluid contents, having an opening for pouring and an opening for admitting air. These openings are sealed on the side of the lid facing out from the container, with a strip of foil joined to the lid. The strip of foil exhibits a feature of originality to show that the container has not been opened in any way at these openings.

6 Claims, 2 Drawing Figures US. Patent Dec. 23, 1975 Fig. 2

TAMPER PROOF SEAL FOR A CONTAINER The inventionconcems a lid for a container which holds fluid contents, the said lid having an opening for pouring out the contents and an opening for admitting air, whereby the said openings are sealed with a strip of foil attached to the side of the lid facing outwards from the container.

For containers for such fluid contents as drinks or oil for example there are basically two well known lid designs. They differ in that one type has incorporated in the design a device to form an opening for both admitting air and for pouring whilst in the other design the openings are already provided in the lid and are subsequently sealed with a covering. The first kind is preferred for contents which are constantly under pressure whilst the latter is used for contents under normal ambient pressure.

The device for producing a combined opening in the lid for admitting air and for pouring consists of a lever device by which means an opening is produced automatically in the lid at the opposite end of the lever from the part which is raised. In another example of this kind an opening is made on tearing away a part of the lid by means of a suitably designed lever device. In the case of contents which tend to deteriorate after air is admitted the user already pays particular attention to the container seal being intact; this gives him the assurance that the contents have not deteriorated. This check is very simply carried out on lids which have a lever device. However this is not so with lids with ready made openings sealed with a covering. The covering is stuck on to the lid and a malicious or accidental damaging of the junction of the covering with the lid, resulting in exposing the opening, is mostly concealed from the user.

The aim of the invention presented here is to produce a suitable covering for a lid for example in the form of a strip of foil which permits the junction between the covering and the container to be checked easily for damageand the object is fulfilled by way of the invention in that the strip of foil exhibits a feature of originality. By a feature of originality is to be understood every measure which allows a manipulation of the strip of foil leading to exposing the opening by loosening the junction of the strip of foil to the lid to be recognized without particularly close inspection being necessary. By providing the lid with a feature of originality the user is given the possibility, just as easily as with lids with opening devices, to convince himself that the container seal is undamaged.

The invention is advantageously so designed that the feature of originality consists of a line of weakness which divides the strip of foil into sections. Clearly visible lines of weakness arranged on the strips of foil present subconsciously to the user focal points for handling the seal, sothat a check on the seal can be limited to the region at and around the lines of weakness. Furthermore to facilitate easier opening of the container by tearing the strip of foil along the lines of weakness, at least two flap-shaped sections are formed which, on peeling away from the container, expose the opening for admitting air and for pouring.

To advantage the lines of weakness consist of a series of perforations spaced apart and passing through the strip of foil. This way the sections are joined together and, by reducing the cross section, the tearing-off is 2 made easier. Since there are bridging pieces between the perforations these bridging pieces are broken when the strips of foil are manipulated, allowing the user to conclude that the contents may be impaired and he can then either decline purchase of the container or make use of the contents.

The invention is further improved in that the line of weakness is arranged to connect the long edges of the strip of foil. This way a shorter cutting path is achieved by making use of a natural division of a strip. The division is to advantage made easier in another design in which the line of weakness runs at an angle to the long edges. The line of weakness and therefore the path along which the tearing takes place is longer by an amount depending on the angle but it has been shown that the tearing then takes place without any problem. A further improvement of the invention is characterised in that the line of weakness runs on both sides into open recesses. Because of these recesses, manipulations of the strips of foil are concentrated even more on the line of weakness. Furthermore the recess assists the raising of part of the strips of foil before tearing off along the line of weakness and help in the making of a It has been found to be of advantage to develop the invention further by surrounding the strips of foil on both sides of the lines of weakness with a region which is not attached to the lid. In this way damage to the line of weakness is made even clearer since parts torn away appear clearly visible by, for example, a crease in a section of the foil strip or by the rolling up of unattached parts. In other respects with this embodiment in making the separation along the line of weakness easier, it is not necessary to overcome the resistance of the bond between the strips of foil and the lid. By way of example one embodiement of the invention is explained in greated detail with the help of the following drawings, viz,

FIG. 1 a lid provided with a strip of foil in accordance with the invention FIG. 2 a sectioned side-view of the lid shown in FIG. 1 FIG. 1 shows by way of example a lid, designed in accordance with the invention, for a round container. The lid can be adapted however for containers of different shape. For the purpose of emptying the contents out of the container the lid 10 possesses an opening 11 for pouring and an opening 12 for admitting air. The pouring opening 11 and the opening 12 for air are sealed by means of a strip of foil 13 which is torn away from the lid 10 to allow the contents to be used.

Depending on the contents the lid and the strip of foil and the container too can be made of various non-metallic or metallic materials. Furthermore various combinations of materials can be used for lid and foil strip. It is however preferred to manufacture the lid and foil strip out of a metallic material, in particular aluminium or an aluminium alloy.

The joining of the foil strip and the lid can among other things take place by applying an adhesive. In the case of a metallic lid and foil strip, before sticking the parts together there is a pre-treatment to allow better bonding between the two metallic faces. The pre-treatment includes the application of an adhesive, or in the case of aluminium a special chemical treatment of the surfaces is carried out. Although the objective of the invention is fulfilled with this kind of lid design, it is preferred use another method of joining.

It has been found particularly favorable in the manufacture of lids designed corresponding to the invention,

to cover the strip of foil with a layer of plastic whichv can be melted and to undertake the joining by heating and melting the plastic layer externally whereby on solidification of the plastic layer the joining is accomplished. The plastics, polyvinylchloride, polyolefine, polyester, polyurethane, epoxyresins, polymers of ethylene grafted with acrylic acid and polyamides of dimeric fatty acids have been shown to be suitable meltible plastic layers for the purposes of the invention. If the contents of the container have to be subjected to sterilization it is preferred to use as meltible plastic a polymer of ethylene grafted with acrylic acid or a polyamide.

To advantage in the case of a foil strip of aluminium; a plastic layer 0.01 to 0.1 mm thick is applied to the strip of foil, whereby the thickness of the strip of foil can amount to 0.02 to 0.35 mm. The thickness of plastic layer and foil strip are determined by the strength of junction required between lid and strip and depends on the contents of the container.

Melting the plastic layer 14 takes place by externally heating the layer 14. So called sealing by which heat and pressure are simultaneously applied to the strip of foil 13, has proved to be successful. Furthermore this joining can also be carried out by the so-called ultrasonic welding, high frequency welding or by the heat impulse process. The advantage of this plastic in connection with the particular joining technology lies in the fact that, unlike the case of joining with adhesives, no pre-treatment to improve the bonding is necessary.

Around the circumference of the lid there is a flanged edge 19 with which a suitable ledge at the free peripheral edge of a container (not shown) engages and the two parts are then rolled together to join the lid 10 to the container.

As a feature of originality the strip of foil 13 is provided with a line of weakness 15 which runs between the long edges of the foil strip 13. The line of weakness consists of a series of perforations side by side, passing through the strip of foil 13, and having between them bridging pieces of foil. In the case presented here the line of weakness 15 runs at an angle of 45 to the long edge of the strip of foil 13. The line of-weakness 15 runs on both sides into recesses 18 provided at the long edges of the strip 13.

It is preferred to provide on both sides of the line of weakness 15 a region 20 which is not joined to the lid. In these regions no junction between the strip 13 and the outside of the lid 10 is made. The region not joined to the lid are those between the broken lines 20, through which the line of weakness runs diagonally. Each of the areas is provided with folds 21, which allow better gripping of the sections 16 and 17 which are in the form of flaps after tearing along the line of weakness l5, and allow the opening 11 for pouring and the opening 12 for admitting air to be exposed.

What is claimed is:

1. A lid for a container holding fluid contents, including a body having an opening for pouring and an opening for admitting air, and a strip of foil connected to said body and disposed for sealing said openings on the side of said body facing out from said container,

the improvement comprising,

said strip of foil consisting of sections divided by a line of weakness to exhibit a feature of originality to show that said container has not been opened in any way at said openings.

2. The lid in accordance with claim 1, characterized in that the line of weakness consists of a series perforations spaced apart from each other and passing through the strip of foil.

3. The lid in accordance with the claim 1 characterized in that the line runs between the long edges of the strip of foil.

4. The lid in accordance with claim 3 characterized in that the line of weakness runs at an angle to the long edges.

5. The lid in accordance with claim 1, characterized in that the line of weakness runs into a recess at each end.

6. The lid in accordance with claim 1, characterized in that the strip of foil possesses a region on both sides of the line of weakness where it is not joined to said body. 

1. A lid for a container holding fluid contents, including a body having an opening for pouring and an opening for admitting air, and a strip of foil connected to said body and disposed for sealing said openings on the side of said body facing out from said container, the improvement comprising, said strip of foil consisting of sections divided by a line of weakness to exhibit a feature of originality to show that said container has not been opened in any way at said openings.
 2. The lid in accordance with claim 1, characterized in that the line of weakness consists of a series perforations spaced apart from each other and passing through the strip of foil.
 3. The lid in accordance with the claim 1 characterized in that the line runs between the long edges of the strip of foil.
 4. The lid in accordance with claim 3 characterized in that the line of weakness runs at an angle to the long edges.
 5. The lid in accordance with claim 1, characterized in that the line of weakness runs into a recess at each end.
 6. The lid in accordance wIth claim 1, characterized in that the strip of foil possesses a region on both sides of the line of weakness where it is not joined to said body. 